Process for the manufacture of low molecular weight polyphenylene ether resins through redistribution

ABSTRACT

The invention relates to a novel process for the manufacture of functionalized polyphenylene ether resins through redistribution with a functionalized phenolic compound in the polyphenylene ether resin polymerization reaction solution without the addition of an added redistribution catalyst or promoter.  
     The invention also relates to the functionalized polyphenylene ether resin made by the process as well as blends and articles containing the functionalized polyphenylene ether resin made by the process.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of the filing date of U.S.Ser. No. 09/245,253, the entire contents of which is hereby incorporatedby reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The invention relates to a novel process for the manufacture offunctionalized polyphenylene ether resins through redistribution with afunctionalized phenolic compound in the polyphenylene ether resinpolymerization reaction solution without the addition of an addedredistribution catalyst or promoter.

[0004] The invention also relates to the functionalized polyphenyleneether resin made by the process as well as blends and articlescontaining the functionalized polyphenylene ether resin made by theprocess.

[0005] 2. Brief Description of the Related Art

[0006] Polyphenylene ether resins (hereinafter “PPE”) are commerciallyattractive materials because of their unique combination of physical,chemical, and electrical properties. Furthermore, the combination of PPEwith other resins provides blends which result in additional overallproperties such as chemical resistance, high strength, and high flow.

[0007] One obstacle to blending PPE with other resins is the lack ofcompatibility between the resins. This lack of compatibility oftenmanifests itself as delamination and/or poor physical properties suchas, for example, poor ductility. One useful method known in the art toimprove the compatibility between resins is to generate reactionproducts between the polymers that will act as compatibilizers for theresins. The reaction products are often thought of as copolymers of theresins.

[0008] One challenge in preparing the aforementioned reaction productsis the need for reactive sites on the resins that will lead to theformation of reaction products. Some polymers such as polyamidesinherently possess both amine and carboxylic acid endgroups that canreadily undergo reaction with another resin containing a wide variety ofpossible reactive moieties. Polymers like PPE contain primarily phenolicendgroups and are in general not sufficiently reactive to result in theaforementioned reaction products in commercially feasible processes.

[0009] It should be apparent that methods and processes to introducefunctionality into PPE are highly sought after. Redistribution, alsoknown as equilibration, of phenolic compounds containing at least onefunctional moiety has been shown to afford PPE having desirablefunctionality. In the redistribution reaction of PPE with phenoliccompounds, the PPE are usually split into shorter units with thephenolic compound incorporated in the PPE.

[0010] In the redistribution reactions illustrated in the art, the PPEis dissolved in a solvent with the phenolic compound and a catalyst,optionally with a promoter, is add to the reaction mixture. Afterheating at elevated temperatures, generally between 60° and 80° C., theredistributed PPE is isolated.

[0011] In order to utilize the redistribution technology in acommercially feasible manner, a process was needed that would minimizethe need for additional processes, reaction vessels, and handling ofPPE. It should be apparent that a process that would take advantage ofthe PPE polymerization process and associated mechanical equipment wouldbe extremely advantageous.

SUMMARY OF THE INVENTION

[0012] The needs discussed above have been generally satisfied by thediscovery of a process for preparing a functionalized PPE throughredistribution with a phenolic compound prior to isolation of the PPEfrom the oxidative coupling reaction mixture and without the addition ofa catalyst or a promoter. The oxidative coupling reaction conditions canbe adjusted to afford sufficient in situ catalyst for the redistributionreaction.

[0013] The description that follows provides further details regardingvarious embodiments of the invention.

DESCRIPTION OF THE DRAWINGS DETAILED DESCRIPTION OF THE INVENTION

[0014] This invention provides for a process for the preparation of lowmolecular weight PPE, preferably having an intrinsic viscosity betweenabout 0.08 dl/g and 0.16 dl/g, by oxidative coupling at least onemonovalent phenol species, preferably at least a portion of which havesubstitution in at least the two ortho positions and hydrogen or halogenin the para position, to produce a PPE having an intrinsic viscosity ofgreater than about 0.16 dl/g as measured in chloroform at 25° C. usingan oxygen containing gas and a complex metal-amine catalyst, preferablya copper (I)-amine catalyst, as the oxidizing agent, redistributing atleast one additional phenol species to produce a PPE having an intrinsicviscosity within the range of about 0.08 dl/g to about 0.16 dl/g, andextracting at least a portion of the metal catalyst as a metal-organicacid salt with an aqueous containing solution, and isolating the PPEthrough devolatilization of the reaction solvent. In one embodiment, theadditional phenol species comprises a functionalized phenol species. Inanother embodiment, the additional phenol species is equilibrated intothe PPE without additional initiator.

[0015] The PPE employed in the present invention are known polymerscomprising a plurality of structural units of the formula

[0016] wherein each structural unit may be the same or different, and ineach structural unit, each Q¹ is independently halogen, primary orsecondary lower alkyl (i.e., alkyl containing up to 7 carbon atoms),phenyl, haloalkyl, aminoalkyl, hydrocarbonoxy, or halohydrocarbonoxywherein at least two carbon atoms separate the halogen and oxygen atoms;and each Q² is independently hydrogen, halogen, primary or secondarylower alkyl, phenyl, haloalkyl, hydrocarbonoxy or halohydrocarbonoxy asdefined for Q¹. Most often, each Q¹ is alkyl or phenyl, especially C₁₋₄alkyl, and each Q² is hydrogen.

[0017] Both homopolymer and copolymer PPE are included. The preferredhomopolymers are those containing 2,6-dimethyl-1,4-phenylene etherunits. Suitable copolymers include random copolymers containing suchunits in combination with (for example) 2,3,6-trimethyl-1,4-phenyleneether units. Also included are PPE containing moieties prepared bygrafting vinyl monomers or polymers such as polystyrenes and elastomers,as well as coupled PPE in which coupling agents such as low molecularweight polycarbonates, quinones, heterocycles and formals undergoreaction in known manner with the hydroxy groups of two poly(phenyleneether) chains to produce a higher molecular weight polymer, provided asubstantial proportion of free OH groups remains.

[0018] The PPE are typically prepared by the oxidative coupling of atleast one monohydroxyaromatic compound such as 2,6-xylenol,2,3,6-trimethylphenol, or mixtures of the foregoing. Catalyst systemsare generally employed for such coupling and they typically contain atleast one heavy metal compound such as a copper, manganese, or cobaltcompound, usually in combination with various other materials.

[0019] It will be apparent to those skilled in the art from theforegoing that the PPE contemplated in the present invention include allthose presently known, irrespective of variations in structural units orancillary chemical features.

[0020] The polymerization of the phenolic monomer may be carried out byadding the phenolic monomer or monomers to a suitable reaction solventand preferably, a copper-amine catalyst. It is preferred to carry outthe polymerization in the presence of a cupric salt-secondary aminecatalyst such as, for example, cupric chloride and di-n-butylamine. Thepolymerizations are advantageously carried out in the presence of aninorganic alkali metal bromide or an alkaline earth metal bromide. Theinorganic bromides may be used at a level of from about 0.1 mole toabout 150 moles per 100 moles of phenolic monomer. These catalystmaterials are described in U.S. Pat. No. 3,733,299 (Cooper et al.).Tetraalkylammonium salts may also be employed as promoters if desired.These promoters are disclosed in U.S. Pat. No. 3,988,297 (Bennett etal.).

[0021] The primary, secondary or tertiary amine component of thecatalyst complex generally correspond to those disclosed in U.S. Pat.Nos. 3,306,874 and 3,306,875 (Hay). Illustrative members includealiphatic amines, including aliphatic mono- and di-amines, where thealiphatic group can be straight or branched chain hydrocarbon orcycloaliphatic. Preferred are aliphatic primary, secondary and tertiarymonoamines and tertiary diamines. Especially preferred are mono-, di-and tri(lower) alkyl amines, the alkyl groups having from 1 to 6 carbonatoms. Typically, there can be used mono-, di- and tri-methyl, ethyl,n-propyl i-propyl, n-butyl substituted amines, mono- anddi-cyclohexylamine, ethylmethyl amine, morpholine, N-(lower) alkylcycloaliphatic amines, such as N-methylcyclohexylamine,N,N′-dialkylethylenediamines, the N,N′-dialkylpropanediamines, theN,N,N,′-trialkylpentanediamines, and the like. In addition, cyclictertiary amines, such as pyridine, alpha-collidine, gamma picoline, andthe like, can be used. Especially useful areN,N,N′,N′-tetraalkylethylenediamines, butane-diamines, and the like.

[0022] Mixtures of such primary, secondary and tertiary amines may beused. A preferred mono alkyl amine is n-butyl amine; a preferred dialkylamine is di-n-butyl amine; and a preferred trialkyl amine istriethylamine. A preferred cyclic tertiary amine is pyridine. Theconcentration of primary and secondary amine in the reaction mixture mayvary within wide limits, but is desirably added in low concentrations. Apreferred range of non-tertiary amines comprises from about 2.0 to about25.0 moles per 100 moles of monovalent phenol. In the case of a tertiaryamine, the preferred range is considerably broader, and comprises fromabout 0.2 to about 1500 moles per 100 moles of monovalent phenol. Withtertiary amines, if water is not removed from the reaction mixture, itis preferred to use from about 500 to about 1500 moles of amine per 100moles of phenol. If water is removed from the reaction, then only about10 moles of tertiary amine, e.g., triethylamine or triethylamine, per100 moles of phenol need be used as a lower limit. Even smaller amountsof tertiary diamines, such as N,N,N′N′-tetramethylbutanediamine can beused, down to as low as about 0.2 mole per 100 moles of phenol.

[0023] Typical examples of cuprous salts and cupric salts suitable forthe process are shown in the Hay patents. These salts include, forexample, cuprous chloride, cuprous bromide, cuprous sulfate, cuprousazide, cuprous tetramine sulfate, cuprous acetate, cuprous butyrate,cuprous toluate, cupric chloride, cupric bromide, cupric sulfate, cupricazide, cupric tetramine sulfate, cupric acetate, cupric butyrate, cuprictoluate, and the like. Preferred cuprous and cupric salts include thehalides, alkanoates or sulfates, e.g., cuprous bromide and cuprouschloride, cupric bromide and cupric chloride, cupric sulfate, cupricfluoride, cuprous acetate and cupric acetate. With primary and secondaryamines, the concentration of the copper salts is desirable maintainedlow and preferably varies from about 0.2 to 2.5 moles per 100 moles ofmonovalent phenol. With tertiary amines, the copper salt is preferableused in an amount providing from about 0.2 to about 15 moles per 100moles of the monovalent phenol.

[0024] Cupric halides are generally preferred over cuprous halides forthe preparation of the copper amine catalyst because of their lowercost. The use of the copper (I) species also greatly increases the rateof oxygen utilization in the early stages of the polymerization reactionand the lower oxygen concentration in the head space of the reactorhelps in reducing the risk of fire or explosion in the reactor. Aprocess for the preparation and use of suitable copper-amine catalystsis in U.S. Pat. No. 3,900,445 (Cooper et al.).

[0025] In the practice of the invention, the catalyst (also known as aninitiator) for the redistribution reaction is preferably generated insitu during the oxidative coupling process. Backward dimer,tetramethyldiphenylquinone (TMDQ), is normally made during coupling of2,6-dimethylphenol and is a preferred catalyst. Other diphenylquinonesmay also be present depending on the phenolic species being oxidativelycoupled.

[0026] Reaction conditions that favor generation of the backward dimerare preferred and can be readily controlled. When the level of monomeris increased during the early stages of oxidation, higher levels of TMDQare produced. Likewise, a slower initial reaction rate with the copper(I) based catalyst also results in an increased accumulation ofunreacted monomer and a increase in the amount of TMDQ produced. Thecopper amine ratio affects the amount of TMDQ generated with a higherratio of amine to copper favoring an increase in the amount of TMDQ.Additionally, allowing the reaction mixture to heat, preferably from thereaction exotherm, also results in higher levels of TMDQ. Generally, thereaction mixture is maintained between about 30° and 45° C., howeverallowing the temperature to increase to even 50° C. results in anincrease in the level of TMDQ. Preferably the level of catalyst is lessthan 10% by weight with respect to the PPE.

[0027] Numerous studies conducted to determine conditions that can leadto increased levels of backward dimer ( e.g., TMDQ) during the oxidativecoupling process have resulted in a number of other unexpected factorsthat affect the formation of backward dimer. First, increasing the ratioof phenolic monomer to solvent (e.g., 2,6-xylenol:toluene ratio) leadsto higher backward dimer ratios as does a high addition rate of phenolicmonomer to the reaction mixture. As previously discussed, increases inthe reactor temperature also leads to increased levels of backwarddimer. Finally, running the oxidative coupling at a lower percentage ofoxygen in the reactor (i.e. a lower phenolic to oxygen ratio) also leadsto increased amounts of backward dimer.

[0028] If no additional functionalized phenolic compound is added at theequilibration step of the process, the TMDQ (or any other backwarddimer) becomes incorporated into the PPE and can lead to a high hydroxylPPE. It should be clear that the present invention also includesprocesses to increase the hydroxyl level on PPE by increasing the levelof backward dimer (e.g., TMDQ) during the oxidative coupling process andincorporating at least a portion of the TMDQ through redistribution(i.e. equilibration). For example, a PPE oxidative coupling reactionthat has a TMDQ level of about six weight percent based on the weight ofthe PPE at the end of reaction had a hydroxyl number of about 360 μmol/gafter equilibration.

[0029] The polymerization reaction is preferably performed in a solvent.Suitable solvents are disclosed in the above-noted Hay patents. Aromaticsolvents such as benzene, toluene, ethylbenzene, xylene, ando-dichlorobenzene are especially preferred, although tetrachloromethane,trichloromethane, dichloromethane, 1,2-dichloroethane andtrichloroethylene may also be used. The weight ratio between solvent andmonomer is normally in the range from 1:1 to 20:1, ie. up to a maximum20-fold excess of solvent. The ratio between solvent and monomer ispreferably in the range from 1:1 to 10:1 by weight.

[0030] The temperature to carry out the polymerization stage of theinvention generally ranges from about 0° C. to about 95° C. Morepreferably, the temperature range is from about 35° C. to about 55° C.with the higher reaction temperature near the end of reaction. Atsubstantially higher temperatures, side reactions can occur leading toundesirable reaction by-products and at temperatures substantiallylower, ice crystals form in the solution. As previously discussed,allowing the reaction mixture to increase above about 50° C. results inan increase in the level of backward dimer produced that can be used tocatalyze the redistribution reaction.

[0031] The process and reaction conditions for the polymerization, suchas reaction time, temperature, oxygen flow rate and the like aremodified based on the exact target molecular weight desired. Theendpoint of the polymerization is conveniently determined with anin-line viscosity meter. Although other methods such as making molecularweight measurements, running to a predetermined reaction time,controlling to a specified end group concentration, or the oxygenconcentration in solution may also be utilized.

[0032] After the end of the oxidative coupling reaction as determined bythe desired molecular weight of the PPE, at least one phenolic compoundis added to the reaction mixture and allowed to circulate whilemaintaining the temperature preferably between about 200 and about 150°C., preferably between about 60° and 80° C. The reaction mixture ismaintained at temperature for about 30 to about 90 minutes, althoughlonger times are possible. During this redistribution step, the flow ofoxygen has been preferably halted as the oxidative coupling has beencompleted. Generally, higher redistribution conversions are obtainedunder air as opposed to nitrogen.

[0033] In the process of the invention, the functionalized phenoliccompound is chosen from the following:

[0034] A) phenolic compounds with formula

[0035] wherein R¹ represents a hydrogen-atom or an alkyl group and Xrepresents an allyl group, an amino group, a protected amino group(e.g., protected by a tertiary-butyl carbonate), a carboxyl group, ahydroxy group, an ester group or a thiol group, wherein R¹ is an alkylgroup when X represents an hydroxy group or an ester group ,wherein Xmay be separated from the phenol ring through an alkyl group and whereinthe total number of carbon atoms in the alkyl groups attached to thephenol ring is not more than six;

[0036] B) bisphenol compounds with formula

[0037] wherein each X, independently of the other X represents ahydrogen atom, an allyl group, an amino group, a protected amino group(e.g., protected by a tertiary-butyl carbonate), a carboxyl group, ahydroxy group, an ester group or a thiol group, with the proviso thatnot more than one X group represents a hydrogen atom, R² and R³represent an hydrogen atom or an alkyl group with 1-6 carbon atoms andeach R⁴ represents independently of the other R⁴ a hydrogen atom, amethyl group or an ethyl group;

[0038] C) a phenolic compound with at least one of the formulas:

[0039] wherein m and n have values from 2-20;

[0040] D) phenolic compounds with formula

[0041] wherein x has a value of 12-20 and y has a value of 1-7 or aderivative thereof;

[0042] E) multifunctional phenolic compounds with formula

[0043] wherein R⁵ represents a hydrogen atom, an alkyl group, an allygroup, an amino group, a protected amino group (e.g., protected by atert-butyl carbonate), a carboxyl group, a hydroxy group, an ester groupor a thiol group; or

[0044] F) phenolic compounds with amino groups with formula

[0045] wherein R⁶ represents independently of one another a hydrogenatom, an alkyl group or a methylene phenol group.

[0046] At the end of the redistribution, the functionalized PPE has alower intrinsic viscosity, and hence a lower molecular weight, than doesthe PPE at the end of the oxidative coupling reaction. The degree of thedecrease is determined at least in part by the amount of phenoliccompound utilized and the amount of catalyst, e.g., TMDQ, present. In apreferred embodiment, the functionalized PPE has a weight averagemolecular weight of at least 1000, preferably between about 3000 andabout 70,000 as compared to polystyrene standards. In another preferredembodiment, the functionalized PPE has an intrinsic viscosity of betweenabout 0.05 dl/g and 0.50 dl/g, preferably between about 0.08 dl/g and0.30 dl/g as measured in chloroform at 30° C. The PPE may have abi-modal distribution of molecular weights.

[0047] Preferably after completion of the redistribution reaction, thecomplex catalyst is chelated to convert the catalyst into a watersoluble metal complex. It is also possible to add the chelating agentwith the phenolic compound or even before the phenolic compound. Ineither case, it is preferable to add the phenolic compound within ashort time frame after the oxygen flow has been discontinued as the TMDQwill begin redistributing and can become consumed before serving as acatalyst for the phenolic compound.

[0048] Many diverse extractants or chelating agents may be used in thepractice of the invention to complex with the catalyst. For example,sulfuric acid, acetic acid, ammonium salts, bisulfate salts and variouschelating agents may be used. When these materials are added to a PPEreaction solution, the copper-amine catalyst becomes poisoned andfurther oxidation does not take place. Many different materials may beused but it is preferred to employ those chelating agents that aredisclosed in U.S. Pat. No. 3,838,102 (Bennett et al.).

[0049] The useful chelating agents include polyfunctional carboxylicacid containing compounds such as, for example, sodium potassiumtartrate, nitrilotriacetic acid (NTA), citric acid, glycine andespecially preferably they will be selected from polyalkylenepolyaminepolycarboxylic acids, aminopolycarboxylic acids, aminocarboxylic acids,aminopolycarboxylic acids, aminocarboxylic acids, polycarboxylic acidsand their alkali metal, alkaline earth metal or mixed alkalimetal-alkaline earth metal salts. The preferred agents includeethylenediaminetetraacetic acid (EDTA), hydroxyethylenediaminetriaceticacid, diethylenetriaminepentaacetic acid and their salts. Especiallypreferred are ethylenediaminotetraacetic acid or a mono-, di-, tri- andtetrasodium salt thereof and the resulting copper complex can bereferred to as a copper carboxylate complex.

[0050] The chelated metallic catalyst component can be extracted withthe water produced in the polymerization reaction by through the use ofa liquid/liquid centrifuge. The preferred extraction liquid for use inthe process of the invention is an aqueous solution of lower alkanol,i.e., a mixture of water and an alkanol having from 1 to about 4 carbonatoms. Generally from about 1% to about 80% by volume of an alkanol orglycol may be employed. These ratios may vary from about 0.01:1 to about10:1 parts by volume of aqueous liquid extractant to discrete organicphase.

[0051] The reaction media generally comprises an aqueous environment.Anti-solvents can also be utilized in combination with the aqueous mediato help drive the precipitation of the copper (I) species. The selectionof an appropriate anti-solvent is based partially on the solubilityco-efficient of the copper (I) species that is being precipitated. Thehalides are highly insoluble in water, log K_([sp])values at 25° C. are-4.49, -8.23 and -11.96 for CuCl, CuBr and Cul, respectively. Solubilityin water is increased by the presence of excess of halide ions due tothe formation of, e.g., CuCl₂, CUCI₃, and CuCl₄ and by other complexingspecies. Non-limiting examples of anti-solvents would comprise lowmolecular weight alkyl and aromatic hydrocarbons, ketones, alcohols andthe like which in themselves would have some solubility in the aqueoussolution. One skilled in the art would be able to select an appropriatetype and amount of anti-solvent, if any was utilized.

[0052] After removal of the catalyst, the PPE containing solution isconcentrated to a higher solids level as part of the isolation of thePPE. Precipitation using standard non-solvent techniques typical for PPEhaving I.V.'s greater than 0.28 dl/g are not generally useful forisolation of low molecular weight PPE due to the small PPE particle sizeand friability of the particles. Very low yields are obtained withundesirable fractionation of oligomeric species. A total isolationprocess is preferred for isolating the PPE. As part of the totalisolation, a portion of the solvent is preferably removed in order toreduce the solvent load on the total isolation equipment.

[0053] Concentration of the PPE containing solution is accomplished byreducing the pressure in a solvent flash vessel while preferablyincreasing the temperature of the PPE containing solution. Pressures ofabout 35 to 50 bar are desirable with solution temperatures increased toat least 200° C., preferably of at least 230° C. A solids level of PPEof at least 55%, preferably of at least 65% or higher is desirable.

[0054] The isolation of the PPE is typically carried out in adevolatilizing extruder although other methods involving spray drying,wiped film evaporators, flake evaporators, and flash vessels with meltpumps, including various combinations involving these methods are alsouseful and in some instances preferred. As previously described, totalisolation is preferably from the viewpoint that oligomeric species arenot removed to the same degree as with precipitation. Likewise,isolation yields are extremely high and are near quantitative. Thesetechniques require however that the catalyst removal be completed in theprior process steps as any catalyst remaining in solution willnecessarily be isolated in the PPE.

[0055] Devolatilizing extruders and processes are known in the art andtypically involve a twin-screw extruder equipped with multiple ventingsections for solvent removal. In the practice of the present invention,the preheated concentrated solution containing the PPE is fed into thedevolatilizing extruder and maintained at a temperature less than about275° C., and preferably less than about 250° C., and most preferablybetween about 185-220° C. with pressures in the vacuum vent of less thanabout 1 bar. The resultant solvent level is reduced to less than about1200 ppm, preferably less than about 600 ppm, and most preferably lessthan about 400 ppm.

[0056] When using a devolatilization extruder for the total isolation ofthe PPE, it was found that traditional underwater or water spray coolingof strands of extrudate followed by chopping the extrudate into pelletsgave unacceptable results presumably due to the low melt strength andinherent brittle nature of low molecular weight PPE. It was found thatspecial pelletization techniques can overcome these difficulties. Usefultechniques include die-face pelletization, including underwaterpelletization and flaking, declining angle strand pelletization usingwater spraying, and vibration drop pelletization with underwaterpelletization especially suitable.

[0057] It was unexpectedly found that underwater pelletization resultedin a significantly lower color in the PPE as compared to the standardstranding with water/air cooling followed by pelletization techniques.Yellowness index (YI) numbers of less than 30, and even less than 25 areachievable as compared to YI>50 achieved with the standard strandingtechnique. It should be apparent that the present process affords amethod of preparing a PPE with a YI of less than about 30, preferablyless than about 25.

[0058] The collected PPE pellets can be dried using techniques standardin the art including centrifugal dryers, batch or continuous ovendryers, fluid beds, and the like. Determination of an appropriate set ofconditions can be readily determined by one of skill in the art withoutundue experimentation.

[0059] One unexpected advantage of the present invention to makefunctionalized PPE is using the inherent backward dimer produced in situby the oxidative coupling reaction to catalyze the redistributionreaction during the polymerization reaction process without a priorisolation of the PPE. This process has advantages for cost reductionsimply by reducing the number of handling steps involved. Moreover, thePPE is subject to fewer heat treatments than isolating the PPE followedby re-dissolving the PPE into a suitable solvent for redistribution. Theprocess also affords a method to make a low molecular weight (i.e. PPEwith an intrinsic viscosity between about 0.08 dl/g and about 0.16 dl/g)functionalized PPE.

[0060] All patents cited by reference are incorporated herein byreference.

[0061] In order that those skilled in the art will be better able topractice the invention, the following examples are given by way ofillustration and not by way of limitation.

EXAMPLES

[0062] Standard PPE Polymerization Procedure

[0063] The catalyst solution can be prepared by stirring 0.41 g ofcuprous bromide and 10.9 g of di-n-butyl amine in 100 ml of toluene. Thecatalyst is transferred to a one liter stirred glass reactor equippedwith an internal cooling coil and inlet tubes for oxygen and monomer. Arapid stream of oxygen is introduced near the bottom of the reactor anda solution of 70 g of 2,6-xylenol in 100 ml of toluene is added througha metering pump, over a period of fifteen minutes, to the rapidlystirred solution. The temperature is maintained at about 30° C. bycirculating water from a constant temperature bath through the coolingcoil. At about 60, about 90 and about 120 minutes after the beginning ofmonomer addition, samples of the reaction mixture are withdrawn, stirredwith a small amount of 50% aqueous acetic acid, centrifuged, and thepolymer solution is decanted. The polymer can be precipitated byaddition of methanol, filtered washed with methanol, and dried undervacuum. Intrinsic viscosities are measured in chloroform solution at 30°C. and are typically measured as 0.29, 0.48, and 0.57 dl/g respectivelyfor the 60, 90, and 120 minutes reaction aliquots.

Example 1.

[0064] Preparation of Functionalized PPE Resin Directly During PPESynthesis

[0065] PPE polymerization was performed according to the standardprocedure using 2,6-xylenol, copper/amine complex, toluene and oxygen.In this example was added 1.48 weight percent of4,4′-bis(4-hydroxy-3,5-dimethylphenyl)pentanoic acid (BX-COOH) per2,6-xylenol at the beginning of the reaction. As the results show (seethe Table below), BX-COOH acts as chain stopper and low molecular weightfunctionalized PPE is prepared. Attempts to prolong the reaction (up to5.5 hours) did not result in any significant increase in molecularweight.

Example 2.

[0066] Preparation of Functionalized PPE Resin Directly During PPESynthesis

[0067] The procedure was repeated according to the Example 1, onlyBX-COOH was added with last portion of 2,6-xylenol that was continuouslyadded over first 40 min of the oxidative coupling reaction. As withExample 1, BX-COOH was a chain stopper and only very low molecular PPEcould be obtained.

Example 3.

[0068] Preparation of Functionalized PPE Immediately After Oxidativecoupling

[0069] The standard PPE preparation has been done according to theExample 1, except that BX-COOH was added immediately after oxidativecoupling (PPE synthesis) was stopped.

[0070] All the products were isolated via standard catalyst removalstep, solvent evaporated and the unreacted BX-COOH was removed bySoxhlet extraction with methanol (15 hours). The products were vacuumdried at 90° C. overnight and characterized.

[0071] The characteristics of all the products are presented in thetable below. Phenol incorporation Phenol der. Mw, g/mol Mn, g/mol Tg, C.% Ex 1 4000 3400 146 54 Ex 2 3700 3200 140 86 Ex 3 22900  11400  203 94

[0072] The above examples illustrate that functionalized PPE may beprepared by the process as described herein utilizing the TMDQ generatedin situ during the oxidative coupling reaction without addition ofadditional catalyst.

What is claimed:
 1. A process to produce a functionalized polyphenyleneether resin, said process comprising: i. oxidative coupling in areaction solution at least one monovalent phenol species using an oxygencontaining gas and a complex metal catalyst to produce a polyphenyleneether resin and a redistribution catalyst, ii. redistributing afunctionalized phenolic compound into the polyphenylene ether resin inthe reaction solution of step i to form a functionalized polyphenyleneether resin, and iii. isolating the functionalized polyphenylene etherresin.
 2. The process of claim 1 wherein the redistribution catalystcomprises a dimer of the monovalent phenol species.
 3. The process ofclaim 1 wherein the redistribution catalyst comprises a diphenylquinone.4. The process of claim 1 wherein the oxidative coupling is done betweenabout 35° C. and about 55° C.
 5. The process of claim 1 wherein thereaction solution in step i is allowed to reach a temperature aboveabout 50° C.
 6. The process of claim 1 wherein the redistribution ofstep ii is done at a temperature between about 20° C. and about 150° C.7. The process of claim 1 wherein the redistribution of step ii is doneat a temperature between about 60° C. and about 80° C.
 8. The process ofclaim 1 wherein the functionalized polyphenylene ether resin has anintrinsic viscosity between about 0.05 dlI/g and about 0.50 dl/g asmeasured in chloroform at 30° C.
 9. The process of claim 1 wherein thefunctionalized polyphenylene ether resin has an intrinsic viscositybetween about 0.08 dl/g and about 0.30 dl/g as measured in chloroform at30° C.
 10. The process of claim 1 wherein the functionalizedpolyphenylene ether resin has a weight average molecular weight betweenabout 3000 and 70,000.
 11. The process of claim 1 wherein thefunctionalized polyphenylene ether resin has a bi-modal distribution ofmolecular weights.
 12. The process of claim 1 further comprising removalof the complex metal catalyst prior to step iii.
 13. The process ofclaim 1 further comprising the step of converting the complex metalcatalyst into a water soluble metal complex.
 14. The process of claim 1wherein step iii comprises precipitating the functionalizedpolyphenylene ether resin.
 15. The process of claim 1 wherein step iiicomprises a total isolation process.
 16. The process of claim 1 whereinstep iii comprises isolating the functionalized polyphenylene etherresin at least in part by devolatilization.
 17. The process of claim 1wherein step iii comprises at least one of spray drying, wiped filmevaporating, and flake evaporating.
 18. The process of claim 1 whereinstep ii occurs prior to isolation of the polyphenylene ether resin ofstep i.
 19. The process of claim 1 wherein the functionalized phenoliccompound is at least one compound selected from the group consisting of:A) phenolic compounds with formula

wherein R¹ represents a hydrogen-atom or an alkyl group and X representsan allyl group, an amino group, a protected amino group (e.g., protectedby a tertiary-butyl carbonate), a carboxyl group, a hydroxy group, anester group or a thiol group, wherein R¹ is an alkyl group when Xrepresents an hydroxy group or an ester group wherein X may be separatedfrom the phenol ring through an alkyl group and wherein the total numberof carbon atoms in the alkyl groups attached to the phenol ring is notmore than six; B) bisphenol compounds with formula

wherein each X, independently of the other X represents a hydrogen atom,an allyl group, an amino group, a protected amino group (e.g., protectedby a tertiary-butyl carbonate), a carboxyl group, a hydroxy group, anester group or a thiol group, with the proviso that not more than one Xgroup represents a hydrogen atom, R² and R³ represent an hydrogen atomor an alkyl group with 1-6 carbon atoms and each R⁴ representsindependently of the other R⁴ a hydrogen atom, a methyl group or anethyl group; C) a phenolic compound with at least one of the formulas:

wherein m and n have values from 2-20; D) phenolic compounds withformula

wherein x has a value of 12-20 and y has a value of 1-7 or a derivativethereof; E) multifunctional phenolic compounds with formula

wherein R⁵ represents a hydrogen atom, an alkyl group, an allyl group,an amino group, a protected amino group (e.g., protected by a tert-butylcarbonate), a carboxyl group, a hydroxy group, an ester group or a thiolgroup; or F) phenolic compounds with amino groups with formula

wherein R⁶ represents independently of one another a hydrogen atom, analkyl group or a methylene phenol group.
 20. The process of claim 1wherein the phenolic compound is 4,4′-(bis(4-hydroxyphenyl) pentanoicacid or derivative of the acid.
 21. The functionalized polyphenyleneether made by the process of claim 1.